All other dependancies are ‘soft’, or trimesh will only fail if a function is called that requires something not installed. If you do the most basic pip install, it will only require those three packages:

# install Miniconda if you have no conda:# https://conda.io/docs/install/quick.html# if you are on Linux and feeling lazy, just run:wgethttps://repo.continuum.io/miniconda/Miniconda3-latest-Linux-x86_64.sh--no-check-certificate-Ominiconda.shbashminiconda.sh-b-p/opt/conda;rmminiconda.shexportPATH="/opt/conda/bin:$PATH"condaupdate-qcondacondacreate-q-nconda_envpython=3.6sourceactivateconda_env# cyassimp is a much faster binding for the assimp importers# they use non- standard labels, master vs main# note that it installs cleanly in Linux and Windows# but generally fails on OSXcondaconfig--addchannelsmenpocondainstall-cmenpo/label/mastercyassimp# install most trimesh requirements with built components from conda-forgecondaconfig--addchannelsconda-forge# rtree, shapely, pyembreecondainstallshapelyrtreegraph-toolpyembreenumpyscipycondainstall-cconda-forgescikit-image# graph-tool is only tested on Ubuntu and very unlikely to work elsewhere# it is used in connected components calculations, and is slighly faster in# most cases than scipy.sparse and networkx (although if graph-tool is not# installed trimesh will automatically use next the fastest option)condaconfig--addchannelsostrokachcondainstallgraph-tool# requires compilation, and fails a lot# used by trimesh.primitives.Extrusion objectspipinstallmeshpy# install trimesh et al (everything except for meshpy, which is separated# above because it fails all the time and is easier to debug individually)pipinstalltrimesh[easy]